BeiGene Ltd. (ONC) shares plunged 5.60% in pre-market trading on Monday, following President Trump's announcement of an executive order aimed at lowering prescription drug costs in the United States. The move has sent shockwaves through the Asian pharmaceutical sector, with BeiGene among the hardest hit.

The sharp decline comes after President Trump declared his intention to sign an executive order implementing a "Most Favored Nation" policy. This policy would tie U.S. government drug prices to those paid by other countries, potentially impacting the profitability of pharmaceutical companies operating in the American market. The announcement has raised concerns among investors about the potential effects on international drugmakers' revenues and profit margins.

BeiGene's pre-market drop is part of a broader trend affecting Asian pharmaceutical stocks. Other major players in the region, including Daiichi Sankyo, Otsuka Holdings, and WuXi Biologics, also experienced significant share price declines. The market reaction underscores the far-reaching implications of U.S. drug pricing reforms on the global pharmaceutical industry, with investors reassessing the valuations of companies heavily reliant on the U.S. market for their revenues.